Where is Fuel Relay for 2004 Dodge Ram 3500 Diesel Truck

James,

Since you are pulling a vacuum to draw the fuel to the fuel pump a very small pin hole will cause the pump to not draw fuel. On my Cummins I connect a fuel line to the tank side of fuel pump and ran it into a pail with diesel fuel to verify an air leak in the line to the tank. The ECM electronics control module on mine a 1999 turns the pump on. You could use a jumper 12 volt to the pump verify it is getting 12 volts. You should be able to hear it running.
I replace the factory fuel pump on mine with a Fass pump and used a small relay to power the Fass pump without using the ECM and it works great.
Keith (waymaker10)

have you check the fuel pump relays and your imobliser if you have one

check the harness plug where it passes behind the drivers side steer tire, in snow areas salt can mess this plug up, check for juice there, and corrosion issues.

A 2004 dodge daully, What model, is it a 2500 or 3500 ? i will also know need to what size engine is in this truck? the last thing is i need to know if this is a gas or diesel and does it have one or two fuel tanks.
Good day

sounds like a ground may not be rite--also chec the plug into the pump for corrosion--relay cud be bad-test it--ask a parts person where you bot the scanner to help you

check for water in the fuel filters and drain them accordingly also check the fuel heater circuit in the fuel filter hosuing to make sure it is working and not shorted check the glow plug relay to mae sure its functioning correctly also

The first thing to do is to start monitoring the coolant level.
This will rule out the possible of headgasket coolant passage pin hole leak.
Headgasket can go at 170,000 miles+ Less if your truck is doing a lot of hauling.
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Have you try Amsoil diesel treatment?
It work well for me.
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I will ran the tank below 1/4 and fill up on NON bio-diesel blend.
Use Chevon diesel until you get the problem figure out.
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Water can come in three way
air condensation in the morning
coolant
fuel.

there is a technical service bulletin to relocate the fuel pump on this vehicle when the transfer pump needs replaced. there is the possibility the transfer pump is going bad on the 2003 now...its not good to run them low or out of fuel

change fuel filter again may have gotten garbage in it and clogged it or if it is diesel lost its prime

Hi. I had the same problem on my 2004 Dodge Ram 3500 Cummins. I went to the dealer and they did a bunch of diagnostics and they replaced my fuel pump. At the same time they put in a retrofit kit that moved the fuel pump to the inside of the gas tank. I have not had the problem since. The cost was about $1,200, but my 100,000 mile drivetrain warranty covered it and I had to pay the $100 deductible.